In an American multivoice system (ZENITH system) which is ordinarily called an MTS system, an audio signal consists of a stereo subchannel, which is AM-modulated to 2f.sub.H (twice the horizontal synchronous frequency), a second audio program (SAP) signal FM-modulated to 5f.sub.H and a pilot signal for stereo broadcast recognition, as well as an audio signal (stereo main channel) of an existing TV system. A characteristic advantage of the American system is that various audio signals can be available since each signal has a different carrier frequency. In other words, when stereo and bilingual broadcasts are simultaneously transmitted from a station, the system allows a consumer to select a desired audio signal.
A video cassette recorder (VCR) for receiving and recording/playing back the audio signal of the MTS system incorporates an MTS decoder for demodulating an MTS signal into stereo and SAP signals prior to recording the demodulated signals on tape. In a high fidelity video tape recorder (VTR), the recording tape has two audio recording regions, i.e., a high fidelity track and a normal audio track. The stereo signal is recorded on the high fidelity track while the SAP signal is recorded on the normal audio track. During reproduction, the stereo or multivoice signal is separately selected by a user. However, the conventional MTS decoder commonly uses a decoder for SAP and stereo signals and decodes information about the selected one of these two signals according to the detection of a pilot signal, which acts as a reference signal. The system then records the decoded information onto a recording medium via a high fidelity audio processor. Since it is impossible to record the stereo and SAP signals simultaneously, the original sound itself cannot be recorded during multibroad-cast when a signal transmitted from the station simultaneously generates the stereo and SAP signals. Accordingly, during reproduction of the recorded program, one signal of the two broadcast signals is omitted.